Mr. Bush was in town promoting his new book "Decision Points." Facebook streamed the interview live on its website and several Facebook employees and friends packed into to hear the 43rd president of the country.

The younger Bush didn't disappoint either. Appearing relaxed and in a button-down shirt and black pants, the former president had a few words of wisdom for Zuckerberg and how to deal with criticism. Facebook was recently the target of user scorn over how it protected members' privacy.

"It just comes with the territory. When you're president, or when you're a successful CEO, you get criticized," he said. "The fundamental question is how you deal with it. And if you believe in what you're doing, then the criticism means nothing."

The president himself said he has no popularity problem these days. He has over 600,000 friends on Facebook.

"I use the Facebook as a way to stay in touch with people who are interested, and who, you know, worked in our administration and are interested in what Laura and I are doing," he said.

That's great news for a man who is "shamelessly marketing" to try and "sell books."